genetic stuff Flashcards
1
Q
biology of heredity
A
- Gametes have 23 chromosomes
- When combined they provide 23 pairs
- First 22 pairs are autosomes and 23d are sex chromosomes
- Each chromosome is made of DNA
- Genes are sections of DNA strands
- Genotype: complete set of genes
- Phenotype: physical, behavioral, psychological features that result from interactions btwn genes and environment
2
Q
single gene inheritance
A
- Genes come in diff forms known as alleles
- Pairs of alleles can be hetero or homozygous
- Dominant allele: chemical instructions followed
- Recessive allele: chem instructions only followed if they are the only ones to follow
- Incomplete dominance: one allele doesn’t completely dominate the other
3
Q
genetic disorders
A
- Many triggered when a child inherits 2 recessive
- Ex. cystic fibrosis, PKU, albinism
- Most are rare
- Some are sex-linked
- Some people are born with too many or too few chormosomes
- Down syndrome → extra 21st chromosome
- Turners syndrome, klinefelters syndrome xyy compliment xxx syndrome cause by missing or extra sex chromosome
4
Q
treating genetic disorders
A
- New medical and surgical techniques performed on fetuses in uterus
o Delivery of drugs or hormones
o Bone marrow transplants
o Surgically repairing genetically transmitted defects of the heart, neural tube, urinary tract, respiratory sytem - Routine screening for PKU and other metabolic disorders with immediate treatment
- PKU → cant metabolize phenolalemine but with a special diet u will b ok
5
Q
behavioral genetics
A
- Genetics that deals with the inheritance of behavioral and psychological traits
- Many behavioral genotypes reflect polygenic inheritance that involves many genes
- Behavioral geneticists use twin studies and adoption studies → see if diff phenotypes btwn environment and biology
- New techniques allow researchers to isolate particular segments of DNA in human chromosomes → serve as markers for identifying alleles
- Research reveals genetic influence in many areas of psychology, including personality, mental ability, psychological disorders, attitudes and interests
6
Q
paths from genes to behaviour
A
- Behavioral consequences of genetic instructions depend on the environment in which instructions develop
- Reaction range: same genotype can produce a range of phenotypes in reaction to environment
7
Q
gene x environment interaction example
A
- Depression and stress: individuals with short version of a genotype labeled 5-HTTLPR (gene involving serotonin) have an elevated risk of developing depression only if they have stressful lives
8
Q
epigenetic view
A
- Heredity and multiple levels of environment (cells to culture) interact dynamically throughout development
- Experiences are influenced by the timing of when genes are expressed
- Timing of genetic expression influenced by experiences
9
Q
cannabis and psychosis
A
- Most cannabis users don’t get psychosis → some vulnerable to effects
- Functional polymorphism in catechol-O-methyltransferase gene moderated influence of adolescent cannabis use on developing adult psychosis
- Carriers of COMT valine allele were most likely to get psychotic symptoms to get schiz if they used pot as teens
10
Q
new epigenetic findings
A
- Early life experiences can produce heritable changes in the gene expression that isn’t coded in DNA itself
- Proteins that regulate genetic activity are regulated by experience
11
Q
meaney and colleagues
A
- If rat moms lick baby lots they are less stressed in life
- Kids exposed to malnutrition early in life have epigenetic alterations regulatory changes in areas of the brain responsible for the HPA axis intensifying the stress response
o Epigenetic changes influence present experience and may be passed on
12
Q
paths from genes to behavior
A
- Genes can influence the kind of environment to which a kid is exposed
- Niche picking: seeking environments that fit heredity
- Environment influences make kids in a family different
- Parents cant provide exactly the same environment for all of their kids
- Kid influences own environment
